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Granitic rocks obtained during field excursions of the famed mineralized regions of the Erzgebirge, Germany (mainly tin-bearing), and South China (mainly tungsten-bearing) have been geochemically analyzed and their results are compared with similar (mainly tungsten-bearing) granites in the island-arc setting of Southwest Japan. The studied granitoids all belong to the ilmenite-series. The collision-related Erzgebirge granitoids are rich in K2O and P2O5, have high A/CNK ratios (1.11-1.24, i.e. S type), but are also high in Ga/ Al ratio (i.e., having some A-type characteristics). In South China, the Xihuashan granites, in contrast, are very low in P2O5, and have A/CNK slightly above 1.0 (1.01-1.05), indicative of I type granites. The ( Sn-) W-related granites of southwest Japan have similarly low P2O5 and A/CNK ratios, indicative also of I-type. Both in the Xihuashan and southwest Japan, the tungsten-related granites have high whole-rock δ18O values implying involvement of W-rich crustal rocks. Sn and W contents of the unaltered granites are lowest in the island-arc setting where the related Sn- W deposits are smallest in size relative to the collision and continental margin settings of the Erzgebirge and South China. [ABSTRACT FROM AUTHOR]